Leona Lewis's tour crew are threatening to quit over her catering policy.

The 25-year-old singer - who has been a strict vegetarian since the age of 12 - has banned all animal products from her 'Labyrinth' shows, much to the fury of her staff, who can't even bring in meat from outside.

A source told The Sun newspaper: "There are going to be murders. Leona has demanded that only veggie food be made available for everyone - and members of the crew are threatening to quit. She will not even allow food to be bought off-site then brought in."

The singer was also blasted for her "out-of-control" diva behaviour.

The insider added: "She is getting a reputation as a bit of a pain in the a**e. She is such a diva. It's getting out of control."

The crew aren't the only people who are unhappy about the ban on meat.

Australian songstress Gabriella Cilmi - who is supporting Leona on the tour - also expressed concern over the vegetarian menu.

Speaking before the start of the tour, she said: "All I know so far is that the food's going to be vegan, and I'm not sure how I'm going to cope with that."